The present invention relates to the production of a semi-synthetic derivative of the antibiotic XK-62-2 and more specifically to the derivative identified as 1-N-[L-(-)-.alpha.-hydroxy-.gamma.-aminobutyryl] XK-62-2.
The method for production and the physicochemical properties of the new antibiotic XK-62-2, which is used as the starting material in the present invention, are described in detail in U.S. patent application Ser. No. 364,058 filed on May 25, 1973.
Briefly stated, XK-62-2, is readily produced by culturing actinomycetes such as Micromonospora sagamiensis, Micromonospora echinospora and Micromonospora purpurea by methods usually employed in the culturing of actinomycetes. More specifically, strains of the above mentioned microorganisms are inoculated into a liquid medium containing a carbon source which the microorganism can utilize such as sugars, hydrocarbons, alcohols, organic acids, etc.; inorganic or organic nitrogen sources and additionally inorganic salts and growth promoting factors, and are cultured at 25.degree.-40.degree. C for 2 to 12 days. Isolation and purification of XK-62-2 is carried out by a proper combination of adsorption and desorption from ion exchange resins and active carbon and column chromatography using cellulose, Sephadex and silica gel. In this manner, XK-62-2 can be obtained in the form of the sulfate or in the free form.
XK-62-2 is a basic substance and is obtained as a white powder. XK-62-2 has a molecular formula of C.sub.20 H.sub.41 N.sub.5 O.sub.7, and a molecular weight of 463. The substance is well soluble in water and methanol, slightly soluble in ethanol and acetone and insoluble in chloroform, benzene, ethyl acetate and n-hexane.